const int emuPin=10;
const int LEDPin=13;
const int intPin=2;
volatile int state=LOW;
void setup() {
  // put your setup code here, to run once:
pinMode(emuPin, OUTPUT);
pinMode(LEDPin, OUTPUT);
pinMode(intPin, INPUT_PULLUP);
attachInterrupt(digitalPinToInterrupt(intPin), blink, CHANGE);
}

void loop() {
  // put your main code here, to run repeatedly:
digitalWrite(emuPin, HIGH);
delay(150);
digitalWrite(emuPin, LOW);
delay(150);
}
void blink() {

  state= !state; 
  digitalWrite(LEDPin, state);
  
}